Radiofrequency ablation and surgical resection of liver metastases from uveal melanoma

Radiofrequency ablation: mechanisms and clinical applications

Radiofrequency ablation (RFA), a form of thermal ablation, employs localized heat to induce protein denaturation in tissue cells, resulting in cell death. It has emerged as a viable treatment option for patients who are ineligible for surgery in various diseases, particularly liver cancer and other tumor-related conditions. In addition to directly eliminating tumor cells, RFA also induces alterations in the infiltrating cells within the tumor microenvironment (TME), which can significantly impact treatment outcomes. Moreover, incomplete RFA (iRFA) may lead to tumor recurrence and metastasis. The current challenge is to enhance the efficacy of RFA by elucidating its underlying mechanisms. This review discusses the clinical applications of RFA in treating various diseases and the mechanisms that contribute to the survival and invasion of tumor cells following iRFA, including the roles of heat shock proteins, hypoxia, and autophagy. Additionally, we analyze‌ the changes occurring in infiltrating cells within the TME after iRFA. Finally, we provide a comprehensive summary of clinical trials involving RFA in conjunction with other treatment modalities in the field of cancer therapy, aiming to offer novel insights and references for improving the effectiveness of RFA.

The Current State of Systemic Therapy of Metastatic Uveal Melanoma

Uveal melanoma (UM) is genetically a distinct tumor compared to cutaneous melanoma (CM), and due to its low mutational burden, it is far less perceptible to the immune system. Thus, treatments that have revolutionized the treatment of CM remain widely inefficient in metastatic UM or only demonstrate effectiveness in a small subpopulation of patients. To this end, the therapeutic benefit of immune checkpoint blockade is very limited and may come at the expense of severe immune-related adverse events that could potentially affect all organ systems. Notably, tebentafusp, an entirely novel class of anti-cancer drugs, has received official authorization for the treatment of metastatic UM. It is the first agent that demonstrated a survival advantage in a randomized controlled trial of metastatic UM patients. Despite the survival benefit and approval, the restriction of tebentafusp to HLA-A*02:01-positive patients and the low objective response rate indicate the persistent need for additional therapies. Thus, liver-directed therapies are commonly used for tumor control of hepatic metastases and represent a central pillar of the daily management of liver-dominant disease. Further, promising data from targeted therapies independent of MEK-inhibitors, such as the combination of darovasertib and crizotinib, raise hope for additional options in metastatic UM in the future. This narrative review provides a timely and comprehensive overview of the current treatment landscape for metastatic UM.

Immunoembolization for the Treatment of Uveal Melanoma Hepatic Metastases

Uveal melanoma is the most common primary intraocular tumor in adults. Approximately 50% of patients develop metastatic disease despite successful treatment of the primary eye tumor. The liver is the most common site of metastatic disease occurring in more than 90% of patients. Clinical prognosis is dependent on the ability to control the growth of liver tumors. Locoregional therapies play an important role in stabilizing liver metastases, prolonging survival for patients with metastatic uveal melanoma. As overall survival is prolonged, the development of extrahepatic disease becomes more common. Immunoembolization, a form of liver-directed therapy, not only focuses on treating hepatic metastases by stimulating the local immune system to suppress the growth of liver tumors, but it potentially generates a systemic immune response delaying the growth of extrahepatic metastases as well. The following article discusses immunoembolization for the treatment of metastatic uveal melanoma including the rationale, mechanism of action, indications, contraindications, outcomes, and associated toxicities.

Surveillance for Metastasis in High-Risk Uveal Melanoma Patients: Standard versus Enhanced Protocols

PURPOSE

to evaluate the effectiveness of enhanced surveillance protocols (EP) utilizing high frequency (HF) or enhanced modality (EM) compared to the standard protocol (SP) in detecting metastasis and determining their impact on overall survival (OS) in high-risk uveal melanoma (UM) patients.

METHODS

A total of 87 consecutive patients with Class 2 (high risk) primary UM were enrolled, with negative baseline systemic staging. The patients underwent systemic surveillance with either SP (hepatic ultrasonography [US] every 6 months) or EP (either HF [US every 3 months] or EM [incorporation hepatic computed tomography/magnetic resonance imaging]) following informed discussion. The main outcome measures were largest diameter of largest hepatic metastasis (LDLM), number of hepatic metastatic lesions, time to detection of metastasis (TDM), and OS.

RESULTS

This study revealed significant differences in LDLM between surveillance protocols, with the use of EP detecting smaller metastatic lesions (HF, EM, and SP were 1.5 cm, 1.6 cm, and 6.1 cm, respectively). Patients on the EM protocol had a lower 24-month cumulative incidence of >3 cm metastasis (3.5% EM vs. 39% SP; p = 0.021), while those on the HF protocol had a higher 24-month cumulative incidence of ≤3 cm metastasis compared to SP (31% HF vs. 10% SP; p = 0.017). Hazard of death following metastasis was significantly reduced in the EP (HR: 0.25; 95% CI: 0.07, 0.84), HF (HR: 0.23; 95% CI: 0.06, 0.84), and EM (HR: 0.11; 95% CI: 0.02, 0.5) groups compared to SP. However, TDM and OS did not significantly differ between protocols.

CONCLUSIONS

Enhanced surveillance protocols improved early detection of hepatic metastasis in UM patients but did not translate into a survival advantage in our study cohort. However, early detection of metastasis in patients receiving liver-directed therapies may lead to improved overall survival.

Liver-directed treatment is associated with improved survival and increased response to immune checkpoint blockade in metastatic uveal melanoma: results from a retrospective multicenter trial

Metastases of uveal melanoma (UM) spread predominantly to the liver. Due to low response rates to systemic therapies, liver-directed therapies (LDT) are commonly used for tumor control. The impact of LDT on the response to systemic treatment is unknown. A total of 182 patients with metastatic UM treated with immune checkpoint blockade (ICB) were included in this analysis. Patients were recruited from prospective skin cancer centers and the German national skin cancer registry (ADOReg) of the German Dermatologic Cooperative Oncology Group (DeCOG). Two cohorts were compared: patients with LDT (cohort A, n = 78) versus those without LDT (cohort B, n = 104). Data were analyzed for response to treatment, progression-free survival (PFS), and overall survival (OS). The median OS was significantly longer in cohort A than in cohort B (20.1 vs. 13.8 months; P = 0.0016) and a trend towards improved PFS was observed for cohort A (3.0 vs. 2.5 months; P = 0.054). The objective response rate to any ICB (16.7% vs. 3.8%, P = 0.0073) and combined ICB (14.1% vs. 4.5%, P = 0.017) was more favorable in cohort A. Our data suggest that the combination of LDT with ICB may be associated with a survival benefit and higher treatment response to ICB in patients with metastatic UM.

Minimally Invasive Treatment Options for Hepatic Uveal Melanoma Metastases

Uveal melanoma is one of the most common primary intraocular malignancies that accounts for about 85% of all ocular melanomas. The pathophysiology of uveal melanoma is distinct from cutaneous melanoma and has separate tumor profiles. The management of uveal melanoma is largely dependent on the presence of metastases, which confers a poor prognosis with a one-year survival reaching only 15%. Although a better understanding of tumor biology has led to the development of novel pharmacologic agents, there is increasing demand for minimally invasive management of hepatic uveal melanoma metastases. Multiple studies have already summarized the systemic therapeutic options available for metastatic uveal melanoma. This review covers the current research for the most prevalent locoregional treatment options for metastatic uveal melanoma including percutaneous hepatic perfusion, immunoembolization, chemoembolization, thermal ablation, and radioembolization.

Sensitivity and Specificity of Different Prognostic Systems in Guiding Surveillance for Metastases in Uveal Melanoma

Uveal melanoma (UM) metastasises in ~50% of patients, most frequently to the liver. Surveillance imaging can provide early detection of hepatic metastases; however, guidance regarding UM patient risk stratification for surveillance is unclear. This study compared sensitivity and specificity of four current prognostic systems, when used for risk stratification for surveillance, on patients treated at the Liverpool Ocular Oncology Centre (LOOC) between 2007-2016 (n = 1047). It found that the Liverpool Uveal Melanoma Prognosticator Online III (LUMPOIII) or Liverpool Parsimonious Model (LPM) offered greater specificity at equal levels of sensitivity than the American Joint Committee on Cancer (AJCC) system or monosomy 3 alone, and suggests guidance to achieve 95% sensitivity and 51% specificity (i.e., how to detect the same number of patients with metastases, while reducing the number of negative scans). For example, 180 scans could be safely avoided over 5 years in 200 patients using the most specific approach. LUMPOIII also offered high sensitivity and improved specificity over the AJCC in the absence of genetic information, making the result relevant to centres that do not perform genetic testing, or where such testing is inappropriate or fails. This study provides valuable information for clinical guidelines for risk stratification for surveillance in UM.

Consensus statement for metastatic surveillance of uveal melanoma in Scotland

Ophthalmic treatments are successful in managing uveal melanomas achieving good local control. However, a large number still metastasise, primarily to the liver, resulting in mortality. There is no consensus across the world on the mode, frequency, duration or utility of regular liver surveillance for metastasis and there are no published protocols. The Scottish Ocular Oncology Service (SOOS) constituted a Scottish Consensus Statement Group (SCSG) which included ocular oncologists, medical oncologists, radiologists and a uveal melanoma patient as a lay member. This group carried out an extensive review of literature followed by discussions to arrive at a consensus regarding surveillance planning for posterior uveal melanoma patients in Scotland. The Consensus Statement would provide a framework to guide each patient's surveillance plan and provide all patients with clarity and transparency on the issue. The SCSG was unable to find adequate evidence on which to base the strategy. The consensus statement recommends a risk-stratified approach to surveillance for these patients dividing them into low to medium-risk and high-risk groups defining the mode and duration of surveillance for each. It supplements the UK-wide Uveal Melanoma National Guidelines and allows a more uniform consensus-based approach to surveillance in Scotland. It has been adopted nationally by all health care providers in Scotland as a guideline and is available to patients on a publicly accessible website.

Liver resection for metastatic uveal melanoma: experience from a supra-regional centre and review of literature

Management of liver metastases from uveal melanoma (LMUM) requires multimodal approach. This study describes evolution of liver resection for LMUM, reviewing current literature and institutional outcomes. Records of patients referred to the Melanoma Multi-Disciplinary Team between February 2005 and August 2018 were reviewed. All publications describing surgery for LMUM were identified from PubMed, Embase, and Google Scholar. Thirty-one of 147 patients with LMUM underwent laparoscopic liver biopsy, and 29 (14 females) had liver resections. Nineteen liver resections were performed locally [7 major (≥3 seg), 14 laparoscopic] without major complications or mortality. Overall survival positively correlated with the time from uveal melanoma to LMUM (Spearman's rho rs  = 0.859, P  < 0.0001). Overall and recurrence-free survivals were comparable following R1 or R0 resections (OS 25 vs. 28 months, P  = 0.404; RFS 13 vs. 6 months, P  = 0.596). R1 resection cohort had longer lead-time (median 100 vs. 24 months, P  = 0.0408). Eleven publications describing liver resection for LMUM were identified and included in the narrative review. Surgery for LMUM is safe and complements multidisciplinary management. Despite heterogeneity in literature, time from diagnosis of uveal melanoma to LMUM remains a key factor affecting survival after liver resection.

Chemosaturation for primary and secondary liver malignancies: A comprehensive update of current evidence

Regional therapies for primary and secondary liver tumors have garnered interest in recent years and several types of treatment approaches have been pursued to control disease, palliate symptoms, and extend survival. Chemosaturation is an innovative way to deliver high-dose chemotherapy to the liver via the hepatic artery. Within the last decade, "isolated hepatic perfusion" (IHP) has evolved from an open surgical approach to a minimally invasive procedure, now termed "chemosaturation" (CS) with "percutaneous hepatic perfusion (PHP)". The most conclusive data on CS-PHP is currently available for patients with hepatic metastases from uveal melanoma (UM) - a rare but devastating disease with a poor long-term survival rate. A global phase-3 study and several cohort studies have provided compelling evidence that CS-PHP is an effective salvage treatment for liver-dominant metastatic UM in institutions with appropriate expertise. In this review we provide an overview on the technique, available clinical data, including safety and efficacy, and potential indications for CS-PHP.

Advances in the clinical management of uveal melanoma

Melanomas arising in the uveal tract of the eye are a rare form of the disease with a biology and clinical phenotype distinct from their more common cutaneous counterparts. Treatment of primary uveal melanoma with radiotherapy, enucleation or other modalities achieves local control in more than 90% of patients, although 40% or more ultimately develop distant metastases, most commonly in the liver. Until January 2022, no systemic therapy had received regulatory approval for patients with metastatic uveal melanoma, and these patients have historically had a dismal prognosis owing to the limited efficacy of the available treatments. A series of seminal studies over the past two decades have identified highly prevalent early, tumour-initiating oncogenic genomic aberrations, later recurring prognostic alterations and immunological features that characterize uveal melanoma. These advances have driven the development of a number of novel emerging treatments, including tebentafusp, the first systemic therapy to achieve regulatory approval for this disease. In this Review, our multidisciplinary and international group of authors summarize the biology of uveal melanoma, management of primary disease and surveillance strategies to detect recurrent disease, and then focus on the current standard and emerging regional and systemic treatment approaches for metastatic uveal melanoma.

Non-colorectal liver metastases: A review of interventional and surgical treatment modalities

Liver metastases (LM) occur in up to 90% either simultaneously with the diagnosis of the primary tumor or at a later time-point. While resection of colorectal LM and resection or transplantation of neuroendocrine LM is part of a standard therapy with a 5-year patient survival of up to 80%, resection of non-colorectal and non-neuroendocrine LM is still discussed controversially. The reason for it is the significantly lower survival benefit of all different tumor entities depending on the biological aggressiveness of the tumor. Randomized controlled trials are lacking. However, reviews of case series with ≥100 liver resections are available. They show a 5-year patient survival of up to 42% compared to only <5% in patients without treatment. Risk factors for poor survival include the type of primary tumor, a short interval between resection of the primary tumor and liver resection, extrahepatic manifestation of the tumor, number and size of the LM, and extent of liver resection. Overall, it has recently been shown that a good patient selection, the technical advances in surgical therapy and the use of a risk score to predict the prognosis lead to a significantly better outcome so that it is no longer justified not to offer liver resection to patients with non-colorectal, non- endocrine LM. Since modern therapy of LM is multimodal, the optimal therapeutic approach is decided individually by a multidisciplinary team consisting of visceral surgeons, oncologists, interventional radiologists and radiologists as part of a tumor board.

Tumor Growth Rate as a Predictive Marker for Recurrence and Survival After Liver Resection in Patients with Liver Metastases of Uveal Melanoma

BACKGROUND

Surgical management of liver metastases of uveal melanoma (LMUM) is associated with the best survival rates, especially for patients with a low tumor burden in the liver. The aim was to determine whether the tumor growth rate (TGR₀) before liver resection helps predict survival in patients with resectable LMUM.

METHODS

This retrospective study included 99 patients with LMUM treated with liver resection between November 2007 and November 2020. TGR₀ was expressed as the percentage change in tumor volume over 1 month according to two pretreatment imaging scans. Multivariate Cox analyses identified independent predictors of disease-free survival (DFS) and overall survival (OS).

RESULTS

DFS and OS had a statistically significant positive linear relationship (Spearman correlation r = 0.68, p < 0.001). A disease-free interval (DFI) > 24 months and a TGR₀ ≤ 50%/month were independent factors associated with better DFS and OS. The 2-component model including TGR₀ and DFI had a mean time-dependent area under the curve (AUC) of 0.81 (95% CI, 0.75-0.86) and 0.77 (95% CI, 0.67-0.87), respectively, for predicting DFS and OS. DFI with TGR₀ defined three kinetic risk groups that had distinct DFS and OS outcomes (p < 0.001). Cytogenetic alterations at baseline were partially predictive factors of the kinetic risk score based on TGR₀ and DFI.

DISCUSSION

The assessment of TGR₀ improves prognostic stratification by identifying patients at high risk of recurrence and poor survival after liver resection. TGR₀ and DFI, reflecting tumor aggressivity, have the potential to be important markers for systemic adjuvant decisions.

Is hepatic resection justified for non-colorectal non-neuroendocrine liver metastases? A systematic review and meta-analysis

BACKGROUND

Hepatic resection (HR) is effective for colorectal or neuroendocrine liver metastases. However, the role of HR for non-colorectal non-neuroendocrine liver metastases (NCNNLM) is unknown. This study aims to perform a systematic review and meta-analysis on long-term clinical outcomes after HR for NCNNLM.

METHODS

electronic search was performed to identify relevant publications using PRISMA and MOOSE guidelines. Primary outcomes were 3- and 5-year overall survival (OS) and disease-free survival (DFS). Secondary outcomes were post-operative morbidity and 30-day mortality.

RESULTS

There were 40 selected studies involving 5696 patients with NCNNLM undergone HR. Pooled data analyses showed that the 3- and 5-year OS were 40% (95% CI 0.35-0.46) and 32% (95% CI 0.29-0.36), whereas the 3- and 5-year DFS were 28% (95% CI 0.21-0.36) and 24% (95% CI 0.20-0.30), respectively. The postoperative morbidity rate was 28%, while the 30-day mortality was 2%. Subgroup analysis on HR for gastric cancer liver metastasis revealed the 3-year and 5-year OS of 39% and 25%, respectively.

CONCLUSIONS

HR for NCNNLM may achieve satisfactory survival outcome in selected patients with low morbidities and mortalities. However, more concrete evidence from prospective study is warrant in future.

Helping Patients Communicate With Oncologists When Cancer Treatment Resistance Occurs to Develop, Test, and Implement a Patient Communication Aid: Sequential Collaborative Mixed Methods Study

BACKGROUND

Most cancer-related deaths result from disseminated diseases that develop resistance to anticancer treatments. Inappropriate communication in this challenging situation may result in unmet patient information and support needs. Patient communication aids such as question prompt lists (QPLs) may help.

OBJECTIVE

This study aims to develop and pilot-test a specific QPL in the following two contrasting clinical contexts in France after cancer resistance has developed: triple-negative and luminal B metastatic breast cancer (MBC) and metastatic uveal melanoma (MUM).

METHODS

A sequential study design with a mixed methods collaborative approach will be applied. The first step aims to build a specific QPL. Step 1a will explore oncologist-patient communication issues from oncology professionals' interviews (n=20 approximately). Step 1b will appraise information and support needs experienced by patients with MBC or MUM both quantitatively (n=80) and qualitatively (n=40 approximately). These data will be used to develop and pilot-test a QPL specific to patients with cancer experiencing initial or acquired resistance to treatment. We expect to obtain a core QPL that comprises questions and concerns commonly expressed by patients with resistant cancer and is complemented by specific issues for either MBC or MUM cancer sites. In step 1c, 2 focus groups of patients with any type of metastatic cancer (n=4) and health care professionals (n=4) will be conducted to revise the content of a preliminary QPL and elaborate an acceptable and feasible clinical implementation. In step 1d, the content of the QPL version 1 and implementation guidance will be validated using a Delphi process. Step 2 will pilot-test the QPL version 1 in real practice with patients with MBC or MUM (n=80). Clinical utility will be assessed by comparing responses to questionnaires administered in step 1b (QPL-naive historical control group) and step 2 (QPL intervention group).

RESULTS

This study received grants in March and December 2019 and was approved by the French national ethics committee in July 2019. As of October 2021, interviews with oncology professionals have been conducted and analyzed (N=26 to reach saturation), and 39 and 27 patients with MBC and MUM, respectively, have been recruited.

CONCLUSIONS

A clinically and culturally tailored QPL is expected to facilitate patients' participation in consultations, improve oncologists' responses to patients' information and support needs, and thus foster patients' psychological adjustment to the diagnosis and follow-up of cancer resistance to treatment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04118062; http://clinicaltrials.gov/ct2/show/NCT04118062.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/26414.

Metastatic uveal melanoma: The final frontier

Treatment of primary intraocular uveal melanoma has developed considerably, its driver genes are largely unraveled, and the ways to assess its risk for metastases are very precise, being based on an international staging system and genetic data. Unfortunately, the risk of distant metastases, which emerge in approximately one half of all patients, is unaltered. Metastases are the leading single cause of death after uveal melanoma is diagnosed, yet no consensus exists regarding surveillance, staging, and treatment of disseminated disease, and survival has not improved until recently. The final frontier in conquering uveal melanoma lies in solving these issues to cure metastatic disease. Most studies on metastatic uveal melanoma are small, uncontrolled, retrospective, and do not report staging. Meta-analyses confirm a median overall survival of 10-13 months, and a cure rate that approaches nil, although survival exceeding 5 years is possible, estimated 2% either with first-line treatment or with best supportive care. Hepatic ultrasonography and magnetic resonance imaging as surveillance methods have a sensitivity of 95-100% and 83-100%, respectively, to detect metastases without radiation hazard according to prevailing evidence, but computed tomography is necessary for staging. No blood-based tests additional to liver function tests are generally accepted. Three validated staging systems predict, each in defined situations, overall survival after metastasis. Their essential components include measures of tumor burden, liver function, and performance status or metastasis free interval. Age and gender may additionally influence survival. Exceptional mutational events in metastases may make them susceptible to checkpoint inhibitors. In a large meta-analysis, surgical treatment was associated with 6 months longer median overall survival as compared to conventional chemotherapy and, recently, tebentafusp as first-line treatment at the first interim analysis of a randomized phase III trial likewise provided a 6 months longer median overall survival compared to investigator's choice, mostly pembrolizumab; these treatments currently apply to selected patients. Promoting dormancy of micrometastases, harmonizing surveillance protocols, promoting staging, identifying predictive factors, initiating controlled clinical trials, and standardizing reporting will be critical steppingstones in reaching the final frontier of curing metastatic uveal melanoma.

Selective internal radiation therapy for hepatic metastases of uveal melanoma: a systematic review

OBJECTIVE

Uveal melanoma (UM) commonly metastasizes to the liver. Treatment usually consists of liver-directed therapies, such as selective internal radiation therapy (SIRT). This review aimed to assess the effectiveness and safety of SIRT for hepatic metastases from UM.

METHODS

The study protocol is available at OSF (https://osf.io/vhyct/). EMBASE and MEDLINE were searched until July 2020, using terms related to SIRT and hepatic metastases from UM. Studies reporting outcomes of SIRT in patients with UM and at least one hepatic metastasis were included. Data on overall survival (OS), hepatic progression free survival (hPFS) or tumor response were collected. The Newcastle-Ottawa Scale (NOS) was used to assess risk of bias.

RESULTS

11 studies were included, reporting outcomes for 268 patients with hepatic metastases from UM. Most studies (n = 9, 81.8%) were retrospective. Disease control was achieved in 170 patients (67.5%) and the median OS from time of SIRT was 12.3 months. Median hPFS was 5.4 months. Low-grade side-effects were common but serious complications were infrequent. There were two treatment-related deaths. The median NOS score was 6 (moderate risk of bias).

CONCLUSION

SIRT appears to be a safe and effective treatment for patients with unresectable hepatic metastases from UM. The certainty of our results is unclear due to predominantly retrospective data with moderate risk of bias. Further prospective studies are required to explore the role of SIRT in UM.

ADVANCES IN KNOWLEDGE

SIRT appears to be a safe treatment for patients with unresectable hepatic metastases from UM. Further prospective work is required.

The What, the Why, and the How of Liver Ablations: A Practical Guide for the Medical Oncologist

Interventional oncology plays a major role within modern oncological patient management. Image-guided thermal ablation has been recognized as a successful local therapeutic option in patients with primary and secondary malignant liver diseases, as also recalled by the recent European Society of Medical Oncology (ESMO) guidelines on colorectal metastases. As image-guided treatments may be as effective as surgery in selected patients with liver lesions, the clinical oncologist should be familiar with the indications, risks, and technical aspects of liver ablation in order to provide their patients with the best outcomes. This article provides a broad overview of the most commonly used ablation techniques and highlights the most relevant technical aspects such as the ideal setting in the operating theatre; which image-guided methods are available, including the growing application of fusion imaging; or contrast-enhanced ultrasound for guiding/monitoring the procedure. A further aim is to expand the knowledge among medical oncologists about liver ablation procedures and to provide insights into the future perspectives of percutaneous minimally invasive procedures in the liver.

An Overview of Liver Directed Locoregional Therapies

An overview of all liver-directed locoregional therapies, including surgical resection for melanoma liver metastases (MLMs), is provided. MLM patients are divided by their primary melanoma location; cutaneous, uvea (eye), and mucosal melanoma. If patients with isolated cutaneous MLMs are considered for surgical resection, treatment with systemic therapy should be part of the treatment course. For uveal MLMs, complete surgical or ablative treatment of all MLMs suggests superior results compared with other liver-directed or systemic therapies, based on current evidence, no recommendations for any liver-directed regional therapy in the treatment of mucosal MLMs can be made.

Locoregional Therapies for the Treatment of Uveal Melanoma Hepatic Metastases

Uveal melanoma is the most common primary intraocular malignant tumor in adults. Approximately 50% of patients develop metastatic disease of which greater than 90% of patients develop hepatic metastases. Following the development of liver tumors, overall survival is dismal with hepatic failure being the cause of death in nearly all cases. To prolong survival for patients with metastatic uveal melanoma, controlling the growth of hepatic tumors is essential. This article will discuss imaging surveillance following the diagnosis of primary uveal melanoma; locoregional therapies used to control the growth of hepatic metastases including chemoembolization, immunoembolization, radioembolization, percutaneous hepatic perfusion, and thermal ablation; as well as currently available systemic treatment options for metastatic uveal melanoma.

Molecular Insights and Emerging Strategies for Treatment of Metastatic Uveal Melanoma

Uveal melanoma (UM) is the most common intraocular cancer. In recent decades, major advances have been achieved in the diagnosis and prognosis of UM allowing for tailored treatments. However, nearly 50% of patients still develop metastatic disease with survival rates of less than 1 year. There is currently no standard of adjuvant and metastatic treatment in UM, and available therapies are ineffective resulting from cutaneous melanoma protocols. Advances and novel treatment options including liver-directed therapies, immunotherapy, and targeted-therapy have been investigated in UM-dedicated clinical trials on single compounds or combinational therapies, with promising results. Therapies aimed at prolonging or targeting metastatic tumor dormancy provided encouraging results in other cancers, and need to be explored in UM. In this review, the latest progress in the diagnosis, prognosis, and treatment of UM in adjuvant and metastatic settings are discussed. In addition, novel insights into tumor genetics, biology and immunology, and the mechanisms underlying metastatic dormancy are discussed. As evident from the numerous studies discussed in this review, the increasing knowledge of this disease and the promising results from testing of novel individualized therapies could offer future perspectives for translating in clinical use.

Treatment of Metastatic Uveal Melanoma: Systematic Review

INTRODUCTION

More than 50% of patients with uveal melanoma end up developing metastases. Currently, there is no standard first-line treatment that facilitates proper management of the metastatic disease.

METHODS

A systematic review of the last 40 years in PubMed with an exhaustive and strict selection of studies was conducted, in which the unit of measurement was overall survival (OS) expressed in Kaplan-Meier curves or numerically.

RESULTS

After the selection process, 110 articles were included. Regional therapies, such as intra-arterial liver chemotherapy (OS: 2, 9-22 months), isolated liver perfusion (OS: 9, 6-27, 4 months), or selective internal radiation therapy (OS: 18 months in monotherapy and 26 months in combination with other therapies) showed some superiority when compared to systemic therapies, such as chemotherapy (OS: 4, 6-17 months), immunotherapy (OS: 5-19, 1 month), immunosuppression (OS: 11 months), or targeted therapy (OS: 6-12 months), without being significant.

CONCLUSIONS

The results of this review suggest that there are no important differences in OS when comparing the different current treatment modalities. Most of the differences found seem to be explained by the heterogenicity of the different studies and the presence of biases in their design, rather than actual extensions of patient survival.

Melanoma liver metastases with special imaging features on magnetic resonance imaging after microwave ablations: How to evaluate technical efficacy?

Purpose

To evaluate the technical feasibility of microwave ablation (MWA) for melanoma liver metastases with persistent high signal on magnetic resonance imaging (MRI).

Materials and Methods

Seven patients with 22 target melanoma liver metastases who underwent MWA treatment were included. All procedure-related complications were observed and recorded. One month after MWA, the imaging features of treated liver metastases and ablation zones with different MRI sequences were reviewed to evaluate technique efficacy. To verify the correctness of the evaluation, MRI scans during patient follow-up were reviewed and compared with images before MWA to analyze changes in treated liver metastases and ablation zones.

Results

All ablations were performed successfully, and there were no procedure-related major complications. After ablation, according to MRI T1-weighted pre-contrast or contrast sequences, the persistence of high signals from the treated lesions was noted inside the ablation zones of 19 lesions. Among these 19 lesions, 17 were completely covered by the ablation zones and were considered successfully treated, whereas two lesions were not completely covered and were considered unsuccessfully treated. Three lesions could not be detected on any MRI sequence after ablation and were also considered successfully treated. Finally, MRI scans during patient follow-up care verified these evaluations.

Conclusion

MWA is a technically feasible option for melanoma liver metastases with special imaging features on MRI.

Uveal melanoma pathobiology: Metastasis to the liver

Uveal melanoma (UM) is a type of intraocular tumor with a propensity to disseminate to the liver. Despite the identification of the early driver mutations during the development of the pathology, the process of UM metastasis is still not fully comprehended. A better understanding of the genetic, molecular, and environmental factors participating to its spread and metastatic outgrowth could provide additional approaches for UM treatment. In this review, we will discuss the advances made towards the understanding of the pathogenesis of metastatic UM, summarize the current and prospective treatments, and introduce some of the ongoing research in this field.

CIRSE Standards of Practice on Thermal Ablation of Liver Tumours

This CIRSE Standards of Practice document reviews current literature and provides best practices for image guided thermal ablation of liver tumours, including radiofrequency, microwave and cryoablation techniques.

Systematic review of liver directed therapy for uveal melanoma hepatic metastases

BACKGROUND

Uveal melanoma (UM) is a rare malignancy with a propensity for metastasis to the liver. Systemic chemotherapy is typically ineffective in these patients with liver metastases and overall survival is poor. There are no evidence-based guidelines for management of UM liver metastases. The aim of this study was to review the evidence for management of UM liver metastases.

METHODS

A systematic review of English literature publications was conducted across Ovid Medline, Ovid MEDLINE and Cochrane CENTRAL databases until April 2019. The primary outcome was overall survival, with disease free survival as a secondary outcome.

RESULTS

55 studies were included in the study, with 2446 patients treated overall. The majority of these studies were retrospective, with 17 of 55 including comparative data. Treatment modalities included surgery, isolated hepatic perfusion (IHP), hepatic artery infusion (HAI), transarterial chemoembolization (TACE), selective internal radiotherapy (SIRT) and Immunoembolization (IE). Survival varied greatly between treatments and between studies using the same treatments. Both surgery and liver-directed treatments were shown to have benefit in selected patients.

CONCLUSION

Predominantly retrospective and uncontrolled studies suggest that surgery and locoregional techniques may prolong survival. Substantial variability in patient selection and study design makes comparison of data and formulation of recommendations challenging.

Development of a Prognostic Nomogram for Liver Metastasis of Uveal Melanoma Patients Selected by Liver MRI

Patients with liver metastases of uveal melanoma (LMUM) die from their metastatic evolution within 2 years. We established a nomogram to choose a treatment adapted to life expectancy. From 2002 to 2013, we reviewed 224 patients with LMUM selected by liver MRI. A nomogram was developed based on a Cox model. The predictive performance of the model was assessed according to the C-statistic, Kaplan–Meier curve, and calibration plots. The median follow-up was 49.2 months (range, 0.6–70.9). The survival rates at 6, 12, and 24 months were 0.88 (0.95 CI [0.84–0.93]), 0.68 (0.95 CI [0.62–0.75]), and 0.26 (0.95 CI [0.21–0.33]), respectively. The four factors selected for the nomogram with a worse prognosis were: A disease-free interval between the UM and LMUM groups of less than 6 months (HR = 3.39; 0.95 CI [1.90–6.05]), more than 10 LMUM (HR = 3.95; 0.95 CI [1.97–4.43]), a maximum LMUM of more than 1200 mm2 (HR = 2.47; 0.95 CI [1.53–3.98]), and a lactate dehydrogenase (LDH) value greater than 1.5 (HR = 3.72; 0.95 CI [2.30–6.00]). The model achieved relatively good discrimination and calibration (C-statistic 0.71). This nomogram could be useful for decision-making and risk stratification for therapeutic options.

Mechanism of miR-137 regulating migration and invasion of melanoma cells by targeting PIK3R3 gene

OBJECTIVE

To investigate the effect of microRNA-137 (miR-137) on the migration and invasion of melanoma cells and its mechanism.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-137 in melanoma tissues and cells. miR-137 mimics, phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) small interfering RNA and corresponding controls were transfected into A375 and WM451 cells by lipofection. The expression of PIK3R3 was examined by qRT-PCR and Western blot analysis. The Trans-well assay was conducted to measure cell migration and invasion. Dual luciferase reporter assay was used to detect the interaction between miR-137 and PIK3R3.

RESULTS

Compared with normal pigmented nevus tissue, miR-137 expression was significantly reduced in melanoma tissues. Compared with keratinous HaCaT cells, the level of miR-137 was significantly decreased in melanoma SK-MEL-1, A375, and WM451 cells. Knockdown of miR-137 significantly reduced the migrated and invasive abilities of melanoma A375 and WM451 cells. Moreover, inhibition of PIK3R3 obviously suppressed the migration and invasion abilities of melanoma A375 and WM451 cells. Luciferase activity assay showed that PIK3R3 was a direct target of miR-137. In addition, overexpression of miR-137-inhibited PIK3R3 expression, while knockdown of miR-137-enhanced PIK3R3 abundance. Restoration of PIK3R3 reversed the regulatory effect of miR-137 on cell migration and invasive in melanoma A375 and WM451 cells.

CONCLUSION

miR-137 inhibited melanoma cell migration and invasion by targeting PIK3R3 gene.

Metastatic Liver Disease: Indications for Locoregional Therapy and Supporting Data

Metastatic liver disease is a major cause of cancer-related morbidity and mortality. Surgical resection is considered the only curative treatment, yet only a minority is eligible. Patients who present with unresectable disease are treated with systemic agents and/or locoregional therapies. The latter include thermal ablation and catheter-based transarterial interventions. Thermal ablation is reserved for those with limited tumor burden. It is used to downstage the disease to enable curative surgical resection, as an adjunct to surgery, or in select patients it is potentially curative. Transarterial therapies are indicated in those with more diffuse disease. The goals of care are to palliate symptoms and prolong survival. The indications and supporting data for thermal ablation and transarterial interventions are reviewed, technical and tumor factors that need to be considered prior to intervention are outlined, and finally several cases are presented.

Role of surgical resection for non-colorectal non-neuroendocrine liver metastases

It is widely accepted that the indications for hepatectomy in colorectal cancer liver metastases and liver metastases of neuro-endocrine tumors result in relatively better prognoses, whereas, the indications and prognoses of hepatectomy for non-colorectal non-neuroendocrine liver metastases (NCNNLM) remain controversial owing to the limited number of cases and the heterogeneity of the primary diseases. There have been many publications on NCNNLM; however, its background heterogeneity makes it difficult to reach a specific conclusion. This heterogeneous disease group should be discussed in the order from its general to specific aspect. The present review paper describes the general prognosis and risk factors associated with NCNNLM while specifically focusing on the liver metastases of each primary disease. A multidisciplinary approach that takes into consideration appropriate timing for hepatectomy combined with chemotherapy may prolong survival and/or contribute to the improvement of the quality of life while giving respite from systemic chemotherapy.

Percutaneous Isolated Hepatic Perfusion as a Treatment for Isolated Hepatic Metastases of Uveal Melanoma: Patient Outcome and Safety in a Multi-centre Study

PURPOSE

Percutaneous isolated hepatic perfusion (PIHP) with Melphalan has been developed as a treatment for patients with isolated hepatic metastases of uveal melanoma. We discuss patient outcome and safety in a retrospective multi-centre study.

MATERIALS AND METHODS

Between 2012 and 2016 18 patients with un-resectable isolated hepatic metastases of uveal melanoma received single or repeated PIHP with Melphalan (n = 35) at seven sites. Progression-free time, overall survival time (OS) and tumour response by means of RECIST 1.1 criteria were evaluated. Peri- and post-procedural adverse events (AE) were registered. Patients' life quality was assessed using four-point scale questionnaires.

RESULTS

Of 18 patients, initial PIHP treatment resulted in partial response (PR) in eight, stable disease (SD) in seven and progressive disease (PD) in three cases. Nine patients underwent second PIHP with PR in eight cases and PD in one case. Six patients were evaluated after third PIHP with PR in five patients and SD in one patient. Two patients received fourth PIHP with PD in both cases. Median OS was 9.6 months (range 1.6-41.0 months). Median progression-free survival time was 12.4 months (range 0.9-41.0 months) with 1-year survival of 44%. Most common post-procedural AE grade 3 and 4 were temporary leukopenia (n = 11) and thrombocytopenia (n = 8). Patients' self-assessments showed good ratings for overall health and quality of life with only slight changes after PIHP, and a high degree of satisfaction with PIHP treatment.

CONCLUSION

PIHP with Melphalan proved to be a relatively safe, minimal-invasive and repeatable treatment for patients with non-resectable hepatic metastases of uveal melanoma.